Building trust in that I’m leaving on Tuesday
Bought a one night stand, just a bootleg
A duplication of something authentic
Play on words: “One night stand, just a boot leg”
A leg (apparently with a boot) is used to stand on, making a double meaning of more than just bootlegging an authentic relationship.
He points out the irony that the only trust (an important part of any relationship) between his girlfriend and him is that he will be leaving some time soon to go off touring again.
The second part of the line refers to how he tries to make himself feel better by having one night stands but they always end up being a disappointing substitute for a real relationship. He is having one night stands which are just sexual relationships. not an “authentic” relationship in which you care about your partner, spend time, and share your life with them. It’s just simulation.
To help improve the meaning of these lyrics, visit "Thin Line" by Macklemore and Ryan Lewis (Ft. Buffalo Madonna & Macklemore) Lyrics and leave a comment on the lyrics box